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<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
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<body>
    <script>
        // 数值类型
        // let number = new Number(99);
        // console.log(number + 1);
        // console.log(number.valueOf());

        // let number = 99;
        // console.log(typeof number);
        // let hd = number.toString();
        // console.log(typeof hd);

        let number = 99.9908;
        console.log(Number.isInteger(number))
        console.log(number.toFixed(2));

    </script>
</body>

</html>